fluent/fluentd — pull request #524 by kiyoto (2014-12-19 21:28:59+00:00)
Title: remove the unused local variable

noticed this while writing a docs.

Another option is to have

```rb
config_param :flush_at_shutdown, :bool, :default => false
```

but that can break backward compatibility (for example, `flush_at_shutdown false` returns different vals.